1. Field of the Invention
The present invention relates to a technique of driving a plasma display panel and, more particularly, to a plasma display panel of an ALIS system and a method of driving this plasma display panel.
2. Description of the Related Art
Recently, as a plasma display panel (PDP) that is capable of obtaining a high definition and a high aperture ratio, there has been proposed a PDP of an ALIS (Alternate Lighting of Surfaces) system. In such a PDP of the ALIS system, there has been a high demand for increasing the gradation display performance by avoiding a distortion in the brightness that is generated depending on a lighting pattern and by preventing the occurrence of an abnormal discharge.
Specifically, the conventional PDP of the ALIS system has a problem in that the linearity of the gradation fails depending on the display pattern. This problem is not limited to a PDP of the ALIS system. A similar problem also exists in a PDP in which there is a short interval between the discharged display lines, and the pitches of the cells are short so that the discharge in the adjacent cells is partially superimposed.
The prior art and the problems associated with the prior art will be described later, in detail, with reference to accompanying drawings.
An object of the present invention is to provide a plasma display panel and a method of driving the same capable of increasing the gradation display performance by avoiding distortion in the brightness that is generated depending on a lighting pattern. It is another object of the present invention to provide a plasma display panel and a method of driving the same capable of preventing an occurrence of an abnormal discharge in the PDP.
According to the present invention, there is provided a method of driving a plasma display panel having a plurality of first electrodes and a plurality of second electrodes adjacently disposed alternately, first display lines being formed between the first electrodes and the second electrodes adjacent to one side of the first electrodes, second display lines being formed between the first electrodes and the second electrodes adjacent to the other side of the first electrodes, the first and second display lines alternately lighting or only one of the first and second display lines lighting, and an image being displayed on the plasma display panel by dividing a frame or a field into a plurality of sub-fields for a gradation display, comprising the steps of carrying out a sustain discharge in a sustain discharge period cells when are lighted on the adjacent first display lines or on the adjacent second display lines in a direction crossing the first and second electrodes; and carrying out a compensation sustain discharge a plurality of times on the second display lines or on the first display lines positioned between the adjacent first display lines or between the adjacent second display lines.
The first electrodes and the second electrodes may be disposed alternately in parallel with each other, and cells that are lighted on the adjacent first display lines or on the adjacent second display lines may be cells on the first display lines or the second display lines that are adjacent to each other in a direction orthogonal with the first and second electrodes. The compensation sustain discharge may be carried out in at least sub-fields in which a sustain discharge is carried out most. The number times of carrying out the compensation sustain discharge is carried out in each sub-field may be allocated in a ratio approximately proportional to the number of sustain discharge. A width of a pulse discharged at the beginning may be set large among the widths of the compensation sustain discharge pulses.
The method may comprise the steps of applying a sustain discharge pulse to cancel the voltage of the second display lines when a sustain discharge is carried out on the first display lines, or, of applying a sustain discharge pulse to cancel the voltage of the first display lines when a sustain discharge is carried out on the second display lines; inverting wall charges of cells where the sustain discharge is carried out by applying an inverted pulse necessary for a discharge only between pairs of electrodes of either odd display lines or even display lines among the first display lines; and carrying out a compensation sustain discharge a predetermined number of times, by applying compensation sustain discharge pulses such that a voltage is generated between electrodes that form display lines where the sustain discharge was not carried out during the sustain discharge period immediately before, and that a voltage is not generated between electrodes that form display lines where the sustain discharge was carried out during the sustain discharge period immediately before.
The width of the inverted pulse may be set larger than the width of the sustain discharge pulse. The voltage of the inverted pulse may be set higher than the voltage of the sustain discharge pulse. A voltage of a pulse discharged at the beginning may be set high among voltages of the compensation sustain discharge pulses. The method of driving the plasma display panel may further comprise the step of applying a voltage pulse necessary for a discharge to only pairs of electrodes of odd or even display lines among the first or second display lines where the compensation sustain discharge is carried out, thereby wall charges of cells where the compensation sustain discharge is carried out is inverted and polarities of wall charges formed on the first electrodes and on the second electrodes are matched on the respective electrodes.
Further, according to the present invention, there is also provided a plasma display panel comprising a plurality of first electrodes; a plurality of second electrodes adjacently disposed alternately with the first electrodes; first display lines formed between the first electrodes and the second electrodes adjacent to one side of the first electrodes; second display lines formed between the first electrodes and the second electrodes adjacent to the other side of the first electrodes; and a control circuit for alternately lighting the first and second display lines or lighting only one of the first and second display lines, and for displaying an image on the plasma display panel by dividing a frame or a field into a plurality of sub-fields for a gradation display, wherein when cells are lighted on the adjacent first display lines or on the adjacent second display lines in a direction crossing the first and second electrodes, a compensation sustain discharge is carried out by a plurality of times on the second display lines or on the first display lines positioned between the adjacent first display lines or between the adjacent second display lines, after a sustain discharge period on the first or second display lines is finished.
The plasma display panel may further comprise a memory for storing the number of times carrying out a sustain discharge on cells that are lighted on the adjacent first display lines or on the adjacent second display lines, and controls the number times of carrying out a compensation sustain discharge on the second display lines positioned between the adjacent first display lines or on the first display lines positioned between the adjacent second display lines, according to the number of times carrying out the sustain discharge stored in the memory.